11 Reasons Why Your Emails Go in the Spam Box (and How to Make Sure They Don’t)

Do you want to know how to stop emails from going to spam? If you have low open rates, it could mean that your emails are getting flagged by spam filters. In this guide, we’ll share 11 reasons why your emails go to spam, and how to make sure they don’t.

According to a 2015 study by Return Path, only 79% of commercial emails actually land in the inbox. That means one out of every five emails sent either gets filtered as spam or blocked entirely.

In fact, the number of successfully delivered emails is on the decline: the global inbox placement rate decreased by 4% from 2014-2015.

So why is it becoming harder to avoid spam filters and keep your perfectly legitimate, non-spam emails from getting marked as spam?

Why Emails Go to Spam Instead of Inbox

One of the big reasons that it is getting harder to avoid emails going to spam is that spam filtering has become more rigorous. Webmail providers are simply cracking down harder on spam. However, the filters aren’t 100% accurate, so sometimes legitimate emails go to spam too.

That’s a part of it, but it’s actually a bit more complicated than that…

You see, subscriber engagement plays a huge role in email deliverability. That’s because webmail providers look at your engagement levels and recipient behavior when determining which emails actually make it to the inbox.

But don’t worry– we’ll explain all of these factors in detail so you can avoid getting flagged and stop emails from going to spam.

Here’s a quick breakdown of what we’ll cover in this guide (feel free to use the links below to jump to that section):

Ready to learn why your emails are landing in the spam folder, and how to keep this from happening? Let’s get started…

11 Reasons Why Emails Go to Spam

There are multiple factors which play an important role in determining whether or not your emails get delivered to the inbox. Let’s dive into the 11 reasons why your emails aren’t getting past the spam filters…

1. You Didn’t Get Express Permission to Email

The #1 rule of email marketing is to get express permission to email first. Never buy a list of email addresses, or you risk violating the CAN-SPAM Act and may be subject to penalties of up to $16,000.

To get express permission, you’ll need an optin form on your site that makes it perfectly clear that your visitors are subscribing to your email list. Download our 63-point optin form checklist to make sure your optin form is set up properly.

Do not manually add emails that you got off of business cards collected at a conference. While you may think that they would appreciate your newsletter, sending emails to them violates the CAN-SPAM Act because they did not give you express permission.

2. Your IP Address Was Used for Spam

Even if you never send spam yourself, your emails could get flagged as spam if your IP address was used by someone else for spam.

For example, if you send your campaigns through MailChimp, your email is delivered through their servers. So if even one other customer sends spam, it could affect your deliverability as well.

(Note, however, that MailChimp is very vigilant about keeping their sending reputation intact, and they have very strict procedures and regulations in place to prevent this.)

3. You Have Low Open Rates

Top webmail providers have stated that they look at how many emails are opened and how many are deleted without being opened as a factor in their spam filtering decisions. This is the top reason for inbox placement issues, effecting 26% of email campaigns incorrectly flagged as spam.

So if you have low open rates, your emails are at higher risk of being flagged as spam.

4. Your Subscribers Don’t Remember You

The second most common reason that emails never reach the inbox (affecting 21% of emails) is spam complaints.

Every time a subscriber reports an email as spam–even if it isn’t really spam–this complaint gets recorded by the mailbox provider. Once the complaints exceed a certain threshold, all future campaigns skip the inbox and get sent directly to the spam folder.

So why would a subscriber flag your email as spam if it isn’t spam? Well, the most likely reason is that they simply don’t remember you. Even though they gave you permission to email them, they don’t remember doing it, so they think you are sending them spam.

To prevent this from happening, make sure that the branding in your emails is memorable, and matches the branding on your website. This includes any images, colors, typography, voice, etc. Also, make sure the “from” line is from a name they will recognize.

If your subscribers don’t immediately remember who you are, you could get spam complaints, so keep that in mind.

Also, make sure to include an easily accessible “unsubscribe” link so that they can opt out if they no longer want your emails.

5. You Have Low Mailbox Usage

The fifth item on our list, and the third most common cause of low inbox placement (affecting 19% of emails), is low mailbox usage.

In their spam filtering algorithms, mailbox providers look at the ratio of active to inactive email accounts on your list. An inactive email account is an account that hasn’t been used in a long time, or is very rarely ever used.

If you are mailing to a large number of addresses that appear to be nearing abandonment, that is a red flag to spam filters.

To prevent this, “clean” your email list periodically of any subscribers who haven’t engaged with your campaigns in a while.

Your email service provider may also include a feature to automatically purge any emails from your list that look like abandoned addresses.

6. Your Subject Line is Misleading

As the CAN-SPAM act states, it is actually against the law to intentionally mislead someone with your subject line in order to induce them to view the message.

In a survey conducted by Litmus and Fluent, over 50% of participants stated that they have felt cheated, tricked or deceived into opening a promotional email by that email’s subject line.

Here are some examples of misleading subject lines:

Did I leave my jacket at your place? – a trick to make it look like they know you.

Thanks for your order! – no order or transaction has actually taken place.

You may be thinking that you’d never resort to these cheap tricks. However, you may be tempted to fall into more of a gray area.

For instance, you might have just written a blog post that you want to send your email list. To get them to open the email, you might include a subject line such as, “8 Reasons You Should Never Post to Social Media”. However, your email says, “Just kidding. I’m not suggesting that you never post to social media. However, here are 8 tips…”

It’s best to avoid these gray areas. Some of your subscribers may be amused but others may not. It’s simply not worth the risk of getting complaints.

7. Your “From” Information is Inaccurate

It’s also against the CAN-SPAM ACT to mislead anyone with your “from”, “to”, “reply-to” and routing information.

For example, if you made your email look like it was from the President, that would be illegal. (An extreme example, but you get the point.)

As a best practice, make sure you do include a name in the “from” field that your subscribers are likely to remember, and don’t change it too often. It could be the name of an individual, your company name, or a combination of the two (e.g. “Syed from OptinMonster”). Whichever you choose, go for memorability and consistency.

8. You Didn’t Include Your Physical Address

Did you know that it is actually against the CAN-SPAM Act to neglect including your valid, physical address?

Your emails must include either your current street address, a post office box that has been registered with the U.S. Postal Service, or a private mailbox registered with a commercial mail receiving agency established under Postal Service regulations.

If you are a small business owner and you work out of your home, we recommend getting a P.O. box for business purposes so you don’t have to mass broadcast your home address.

9. You Didn’t Include an “Unsubscribe” Link

No matter how valuable you think your email campaigns are, you still need to give your subscribers a potential out. If you don’t, you could get spam complaints (at best), or slapped with thousands of dollars in fines.

At the bottom of your emails, include an “unsubscribe” link, or a similar opt-out feature.

Also, when someone asks to be removed, you need to honor that request promptly. Specifically, you must process that request within 10 business days.

You can’t charge a fee for this, ask for any information beyond an email address, or make the subscriber take any step other than sending a reply email or visiting a single page on your website.

For example, you can’t make subscribers fill out a form that explains why they are opting out before they can unsubscribe. If you do want to survey your unsubscribers, show them the survey right after they have successfully opted out or in the unsubscribe confirmation email, not before.

Never sell or transfer the email addresses of your unsubscribers to another mailing list.

10. You Used Spam Trigger Words

Some spam filters are triggered by certain words in the subject line or the body of the email. Some spam trigger words include:

amazing

cancel at any time

check or money order

click here

congratulations

dear friend

for only ($)

free or toll-free

great offer

guarantee

increase sales

order now

promise you

risk free

special promotion

this is not spam

winner

Your email provider may have a built-in tool that checks your emails for spam trigger words before sending it. Alternatively, you can also use ISnotSPAM, a free tool which scores your emails for deliverability and see if they are likely to trigger spam filters.

Simply send your email to the email address displayed on their website, and then click on the View Your Report button.

The report will show you the criteria they looked at, along with your score and whether you passed or failed the test.

11. Your HTML Emails Don’t Follow Best Practices

If you are sending text-only emails, you don’t have to worry about this. However, you may want to send HTML emails as well as a text-only version. That way, you can include some branding elements that make your emails more memorable (which helps with engagement).

We’ve actually tested plain text versus branded emails with our email list, and found that the branded emails actually get higher engagement. So it’s definitely a good thing to try with your own list.

However, you need to follow some best practices for sending HTML emails so they don’t get marked as spam:

Use a maximum width of 600-800 pixels. This will make them look good in most email clients.

Keep your HTML code as simple and clean as possible. If you are using a template from a reputable email service provider, you should be OK.

Keep your image-to-text ratio low. Images are OK to include in your email marketing campaigns, but never send image-only emails with no text.

Optimize your images for email by compressing them first. Don’t use super high resolution images or other media with a large file size.

Don’t use obscure fonts. Stick with fonts that work across platforms, like Arial, Verdana, Georgia and Times New Roman.

Optimize for mobile. Make sure your emails are readable and load quickly on mobile devices, and that your links can be pressed easily with a thumb.

To give you an example, here is one of the branded, HTML emails that our subscribers love:

See how simple it is? We include our logo at the top for brand recognition, but most of the email is text. We also use a simple visual cue, the gray box at the bottom, to highlight the “You are receiving this email because…” area. This makes the email scannable, and reminds subscribers about the benefits of being on our email list.

How to Avoid Emails Going to Spam (3 Steps)

So far, we’ve shown you 11 reasons why your emails go to spam. Next, we’ll show you 3 simple steps to prevent it from happening…

Step 1. Instruct Subscribers to Whitelist Your Emails

In your welcome email that you send to new subscribers after they opt in, make sure to tell them to whitelist your emails.

This will ensure that your subscribers are receiving the important emails they signed up for. Also, having more people whitelist your emails will help to increase your sender reputation, and your inbox delivery rates will be higher overall.

Feel free to copy and paste the following instructions into your welcome email…

How to Whitelist an Email Address with Gmail

Open the email

Click on the drop down arrow next to the “Reply” button

Select “Add to Contacts List”

Click on the “More” button above the email header

Select “Filter messages like these”

At the bottom of the search window, click “Create filter with this search”

Step 3. Teach Them How to Keep Your Emails Organized in a Special Folder

Your emails are important to your subscribers, but they probably also receive a lot of other emails from various subscriptions. Help them to find your emails easily by teaching them how to organize your emails into a special folder.

Also, remember that engagement is a big factor that can affect your inbox placement rates. Helping your subscribers keep track of all your future emails will help keep your emails out of spam for good.

Give your subscribers the following instructions to help them organize emails from you…

Instructions to Organize Emails

Create a special folder where you can archive emails from us after you have read them.

Do not set up filters to automatically direct our emails into these folders, otherwise, you may miss something.

After you have finished reading an email, manually move it to the folder.

Spam Filter Testing and Spam Checkers

Are you still worried that your emails might go to spam? If you follow all of the above tips, and you are still having a problem with emails getting sent to spam, here are some spam checkers that you can use to test your emails for issues.

1. Litmus

Litmus is a suite of email optimization tools which includes a spam checker. Here’s how it helps you keep emails going to spam:

Scans your emails by all the major spam filters before sending, to make sure that they pass.

Checks your reputation by looking at your IP addresses and any domain names used in your email, and checking them against known blacklists. (If any of them could affect your delivery, you’ll get a notification.)

Verifies that your email authentication, such as DKIM, DomainKeys, SenderID, and Sender Policy Framework, is set up properly.

Gives you a spam score, which advice on why you got that score and how to improve it.

2. EmailReach

EmailReach is a comprehensive spam checker and email testing tool. It helps you keep your emails out of spam by:

Notifying you of successful deliveries, delivery failures, and junk folder issues at all major inboxes.

Assessing the content of your emails and design against major spam filters and giving you a spam score.

Checking your IP address and domain reputation against all major email blacklists.

3. IsNotSpam.com

IsNotSpam.com is a free spam checker that you can try if you don’t have the budget for Litmus or EmailReach.

You’ll have to check each mail manually, and it doesn’t have a comprehensive testing capability, but it will check your Sender Policy Framework, SenderID and DKIM to make sure they are set up properly, and it will do a SpamAssassin check to score your email content.

That’s it! We hope this post helped you to learn 11 reasons why your emails go in the spam box, and how to avoid spam filters.

Comments

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Your blog timing is perfect, Mary. Reading through your tips helped me solve the problem of why my previous emails were not arriving. The acronym was too close to another popular one. Business owners who focus on email marketing may not understand why emails don’t arrive in a recipient’s inbox. I’m wondering if the CAN-SPAM act affects anyone emailing people in Canada, as well as doing business here. Thank you for your wealth of info! ~Keri

Thanks Mary – I sadly contacted CASL this week to report an out of control email incident. On the plus – I’ve been telling others about the amazing blogs you and the guest authors write on this site. Not only are your blogs well researched, but the tips shared are useful, relevant and doable. My instinct is that your target audience would really appreciate reading and learning from these blogs. ~Keri

CAN SPAM does not require expressed opt-in as you state in the first section. While it is definitely good to get it, CAN SPAM operates on a “have not opted out” philosophy. CASL however you need explicit opt-in to a specific email stream. If I am wrong, please point me to where it says that exactly so I can change things asap!

You are correct, the CAN-SPAM Act doesn’t require senders to get the recipients’ consent first, but that is a very bad practice that we absolutely do NOT recommend. You also risk violating the CAN-SPAM Act if the emails you obtained were harvested (which is illegal), or if some of the senders had already opted out to receiving emails from your company. You can read about the risks of buying email lists here on the FTC’s website.

Again, we strongly advocate permission based marketing and urge you to NEVER purchase an email list!

The best approach is to use a reputable email service provider so you avoid deliverability issues when sending to a large list, Maria. WPBeginner’s list of the best email marketing services is a good starting point.

Subscriber engagement is improves your sender reputation, Joe, but there’s no absolute guarantee. The best bet is to ask subscribers to whitelist your emails, as suggested in our first tip, so your emails get delivered. And here are some tips to boost email deliverability.

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